The present invention relates to vehicle doors and particularly to a modular door assembly.
In recent years, efforts have been made to improve the quality of vehicle construction as well as reducing the cost of not only manufacturing the vehicle but the cost of operating the vehicle by reducing the weight of the vehicle and, therefore, the energy required for its use. In the past, door assemblies typically were manufactured utilizing a door frame having an outer metal skin. An inner cover plate to which most of the door mechanisms, including window lift assemblies, locks, hinges and the like, were mounted was then positioned over the door frame and subsequently a trim panel attached to the door. In recent years in order to facilitate assembly and control the quality of vehicle door mechanisms, doors have been manufactured utilizing an outer skin and frame which does not include the control mechanism but separately mounted thereto is a carrier plate with the window lift mechanism, the door latching mechanism and the like mounted thereto. This carrier plate is subsequently inserted into the door, secured thereto and a trim panel subsequently covers the interior surface of the resultant door assembly. Although this construction allows better control of the quality of the mechanism mounted on a separate carrier plate, the resultant structure is still relatively heavy and requires assembly of the carrier plate to the vehicle door during manufacture as well as subsequent assembly of the trim panel to the door.
Yet another approach has been suggested in which a relatively rigid trim panel is employed and includes sufficient reinforcement such that the window lift mechanism, door latching mechanism and the like can be mounted directly to the trim panel, which is finished as a subassembly and attached directly to the outer door member. This construction, thus, provides a two-piece door construction in which the inner trim panel and associated operating hardware, including the window and its control mechanism, the door latch and the like, can be made as a single module and subsequently attached to the door during manufacture. This construction is shown in U.S. patent application Ser. No. 08/760,787, entitled DOOR CONSTRUCTION AND METHOD OF ASSEMBLY, filed Dec. 5, 1996, now abandoned the disclosure of which is incorporated herein by reference. Although this construction provides for the quality control of the various components of the door assembly and reduces the overall cost, the trim panel is still a relatively thick structure requiring the use of somewhat expensive materials. The weight, although reduced from prior constructions requiring carrier plates, is still somewhat heavy.
Thus, there remains a need for a modular door assembly which is both lightweight, modular in construction and, therefore, easy to assemble in the assembly plant and yet relatively inexpensive.
The door module of the present invention satisfies this need by employing the control mechanism for the window lift structure as a frame or skeleton to which a relatively thin trim panel is mounted, thereby eliminating the necessity of thick structural trim panels or carrier plates for the window assembly. By coupling the window assembly structure to a single horizontally extending cross member, sufficient structural rigidity is provided to the door panel which can subsequently be mounted to a conventional door outer skin and frame as a modular unit. In a preferred embodiment of the invention, the door module includes a Π-shaped skeleton made of a pair of window lift arms extending downwardly from an upper horizontally extending reinforcement strut to which a relatively thin trim panel is secured with the combination then being attached to a vehicle metal door frame and skin in a conventional manner. In other embodiments, a single arm window lift assembly extends downwardly from a horizontally extending strut and a supplemental reinforcing arm is provided and coupled to a relatively thin trim panel to complete the construction. Thus, a modular door system of the present invention can be employed with single or dual arm window lift mechanisms and provides an extremely lightweight, relatively inexpensive modular door construction which recognizes and utilizes the structural window lift mechanism itself as its structural support, thereby eliminating additional reinforcing structure.
These and other features, objects and advantages of the present invention will become apparent upon reading the following description thereof together with reference to the accompanying drawings.